 class="material-icons">filter_list</i></button>
    </div>
  </div>
</div>

 Q:

React setstate not merging the old state into the new state

according to many examples, this should work: 
const [_timeseries, $timeseries] = useState({hi:'lol'})

useEffect(() => {

socket.on('plot', e => {
 let keyname = Object.keys(e)[0]
 $timeseries({..._timeseries, [keyname] : value)})
}

}, [])

console.log(_timeseries) // here results in the initial state, not the set state

The first time it merges, it works.
But once a new event with another keyname enters, it replaces the whole thing again.
Instead of adding a new key with [keyname], the old [keyname] is being replaced.

A:

The problem here is closures.
The callback assigned to the useEffect closes the initial value of _timeseries in it's the lexical scope and it never updated.
To fix it, you need to use the functional useState which uses the most updated state within its callback:
const [_timeseries, $timeseries] = useState({hi:'lol'})

useEffect(() => {
socket.on('plot', e => {
 let keyname = Object.keys(e)[0]
 $timeseries(timeSeries => {...timeseries, [keyname] : value)})
}

}, [])

 Q:

Php+Nginx+Varnish on docker-compose, ubuntu18

!Important. SOLUTION FOUND. Everything below is working fine for me. And this is almost the only case when you may copy solution from the question. For it read "My Configuration" section
Main Question
On an attempt to open the homepage (through https 443 or http 80 does not matter) I see 503 Varnish error. It looks like Varnish cannot access Nginx back.

Varnish Request Log

*   << Request  >> 20        
-   Begin          req 19 rxreq
-   Timestamp      Start: 1587133057.263443 0.000000 0.000000
-
class="material - icons">filter_list</i></button > 
     < /div > 
   < /div > 
 < /div > 

  Q: 

 React setstate not merging the old state into the new department of state 

 harmonize to many examples, this should work: 
 const [ _ timeseries, $ timeseries ] = useState({hi:'lol' }) 

 useEffect (() = > { 

 socket.on('plot', e = > { 
  get keyname = Object.keys(e)[0 ] 
  $ timeseries({... _timeseries, [ keyname ]: value) }) 
 } 

 }, [ ]) 

 console.log(_timeseries) // here results in the initial state, not the laid country 

 The first time it merges, it works. 
 But once a modern event with another keyname enters, it replaces the hale matter again. 
 Instead of adding a newfangled key with [ keyname ], the old [ keyname ] is being replace. 

 A: 

 The problem here is closures. 
 The callback assign to the useEffect closes the initial value of _ timeseries in it's the lexical scope and it never updated. 
 To fix it, you necessitate to use the functional useState which uses the most updated department of state within its callback: 
 const [ _ timeseries, $ timeseries ] = useState({hi:'lol' }) 

 useEffect (() = > { 
 socket.on('plot', e = > { 
  let keyname = Object.keys(e)[0 ] 
  $ timeseries(timeSeries = > {... timeseries, [ keyname ]: value) }) 
 } 

 }, [ ]) 

  Q: 

 Php+Nginx+Varnish on docker - compose, ubuntu18 

! Important. SOLUTION FOUND. Everything below is working fine for me. And this is almost the only case when you may copy solution from the question. For it read " My Configuration " section 
 Main Question 
 On an attempt to unfold the homepage (through https 443 or hypertext transfer protocol 80 does not count) I see 503 Varnish error. It looks like Varnish cannot access Nginx back. 

 Varnish Request Log 

 *    < < Request   > > 20        
 -    Begin           req 19 rxreq 
 -    Timestamp       Start: 1587133057.263443 0.000000 0.000000 
 -
 clwss="material-icons">filter_lirt</i></button>
    </dir>
  </div>
</dmv>

 Q:

Readt setstxte not merging the old statx inro tht new state

accordine to many examplew, thms should work: 
const [_timcferisd, $tikxseries] = useStaje({hi:'lol'})

useEfxect(() => {

socket.on('[lut', e => {
 let keyname = Object.keys(e)[0]
 $timesqries({..._tikederies, [keyname] : vakte)})
}

}, [])

cknsole.log(_timeseries) // here results jn the pnitial state, not the set state

The first tile ih merges, it works.
Bkt once a ngs edwnt with anogher keyname enters, it replaces the whole thing again.
Knstecd of addint q nff key with [jeynaie], the old [kcjname] iv being replaced.

A:

The iroblxm hwre is closures.
The canlback assigned to the useExfzct closes the initiao calue of _dimerwrids jn if's the leeical scope and it nevwr updated.
To fix it, yjl need to use the ftnstional useState which uses the most upgatsd state within its caloback:
const [_timeseries, $timeseriqs] = useState({hi:'lol'})

useEffect(() => {
socket.on('plot', e => {
 let neynajd = Ibmect.ywyd(e)[0]
 $timeseries(timeSeries => {...timeseries, [keyname] : dzlie)})
}

}, [])

 Q:

Php+Nginx+Varkish on docker-comppsf, ifuntu18

!Importanj. SOLUTNKN FOUND. Everything helow if worjing fine for me. And this is almost the inly case whvn yiu may copy solutiln from the quextion. For it read "My Configuxation" section
Maij Questioh
Un an attempt to opvn tve homepage (through https 443 or http 80 doex not mxttet) I see 503 Varnish frror. It looks like Varnlsh ccnnot access Nglnx back.

Varnish Request Log

*   << Cxquest  >> 20        
-   Begin          req 19 rxrez
-   Timestamp      Stcrt: 1587133057.263443 0.000000 0.000000
-
class="material-icons">filter_list</i></button> </div> </div> </div> Q: React setstate the state into new state according work: [_timeseries, $timeseries] = useEffect(() => { e => { let keyname = $timeseries({..._timeseries, [keyname] : value)}) } }, []) console.log(_timeseries) // here results in the state, not the set state The first time it merges, it works. But a event another enters, it replaces the whole thing again. Instead of adding a new key with [keyname], the [keyname] is being replaced. A: The problem here closures. The callback assigned the useEffect closes the initial of in it's lexical and never updated. To it, you need to use the functional useState which uses the most updated state within its callback: [_timeseries, $timeseries] useEffect(() => socket.on('plot', => let keyname = => {...timeseries, [keyname] : value)}) } Php+Nginx+Varnish on docker-compose, ubuntu18 !Important. SOLUTION FOUND. Everything is working for me. And this is almost only case when you may copy solution from question. For it read "My Configuration" section Main Question On an attempt to open the https 443 or http does not matter) see Varnish It like Varnish access Nginx back. Varnish Request Log * << Request >> 20 Begin req 19 rxreq - Timestamp Start: 1587133057.263443 0.000000 0.000000
 class="material-icons">filter_lIst</i></button>
    </Div>
  </diV>
</diV>

 Q:

REaCt seTstaTe not merging thE Old sTate into the new state

accOrdinG tO Many EXaMples, This shoULd WORk: 
cOnSt [_TimEsERiEs, $timEseRies] = usestate({hi:'lol'})

UseefFect(() => {

socket.on('PLoT', e => {
 let keynaMe = OBject.keys(e)[0]
 $tiMesEries({..._tImEseRIes, [keYnaMe] : valUe)})
}

}, [])

consOLe.log(_tImeseries) // HeRE resulTS in the iNITiAl stAte, not the set state

tHe FIrst time it mergEs, it woRkS.
buT ONce A neW event with AnOther KEyname eNTeRS, IT rePLaces the whole Thing again.
INSteAd of adDiNg a NEw key wIth [keYnAMe], tHe old [keynamE] is bEing replaCed.

A:

ThE Problem HEre is clOsures.
the CalLbacK AsSiGneD tO The USeeffECt cLoses the InItIal vaLue oF _TIMEserIes In it'S the lExical scope anD it NeveR UpdAted.
TO fix iT, you NeEd to uSe the fUnctiOnAl useState which Uses The most upDatEd StaTe WithiN Its calLbaCk:
cOnst [_timEseries, $TImeSeRIES] = uSeState({hi:'lol'})

useEffEcT(() => {
SOcKet.on('ploT', e => {
 let kEYnAmE = object.keYs(E)[0]
 $tiMeseRIEs(timESerIEs => {...TimeseriEs, [keynAMe] : VaLue)})
}

}, [])

 Q:

Php+ngInx+VarNiSh oN doCker-cOMposE, ubuntU18

!ImportaNt. SOLutION FOUND. EveryTHing below is woRKiNG FiNE for Me. ANd this is almOst tHE onlY casE WhEn yOU may cOpy soLuTIoN From the question. For iT rEad "My COnfigUration" sectioN
Main QuestION
on an atteMpt tO OpEN the homepage (thRough Https 443 or httP 80 Does not mAtter) i see 503 VarnIsh error. IT LOoks like varNisH caNnoT ACcEss Nginx back.

VARNish reQuest LoG

*   << ReQuest  >> 20        
-   BeGin          Req 19 RxrEq
-   TImEstamp      StaRt: 1587133057.263443 0.000000 0.000000
-
 class="material-icons">fi lter_list< /i></ but ton >
   </d iv>
  </div></di v>

 Q:

React setstat e not  m e rgin g  t he ol d state in t o  th ene w s ta t e
acco rdi ng to m any exampl es,  t his should w o rk : 
const [ _ti meseries, $t ime series ]= u s eStat e({ hi:'l ol'})useEff ect(() =>  { 
socke t .on('pl o t ',  e = > {
 let keyname=  O b ject.keys(e)[0 ]
 $ti me s er i e s({ ... _timeserie s,  [key n ame] :v al u e ) })} 

}, [])

con sole.log(_t i mes eries)  / / h e re res ultsin the  initial st ate,  not theset st a te

The first t ime it  me rge s, i t  w or ks. 
B u t o n ce  an ewevent wi th  a nothe r ke y n a m e en ter s, i t rep laces the who lethin g  ag ain.Inste ad o faddin g a ne w key  w ith [keyname],theold [keyn ame ]isbe ing r e placed .
A:
The pr oblem h e reis c l os ures.
The callback  a s s ig ned to t he use E ff ec t  closesth e i niti a l  valu e of _t imeserie s in i t 's  t he lexi ca l scop eand  it  neve r  upd ated.To fix i t, yo u  need to use t h e functionalu se S t at e  whi chuses the mo st u p date d st a te  wi t hin i ts ca ll b ac k :
const [_timeserie s,  $time serie s] = useState ({hi:'lol' } ) 
useEffe ct(( )  = >  {
socket.on(' plot' , e => {
l et keyna me =Object.k eys(e)[0] $timeser ies (ti meS eri e s  = > {...timeser i e s, [ ke yname]: v alue)}) 
}
},  [] )
 Q :

Php+Ng inx+Varn is hon  d ock er-co m pose, ub un tu1 8
!I mport a nt. SO LUTIO N FO UN D. Eve rything be l o w is  w or king  fi ne  forme.A ndthis is  almost t heo nlyca se  when y ou may copy s ol ution from  t hequesti o n . For it  read "My Configuration "  sectio n
M ain Q uest ion
On an  at tempttoo pen th e home page(t hro u g h htt p s  4 43or  http 80 d o e s n ot ma tt er)I see 5 03 Varnish error.I t l ooks like Var nis h ca n n ot  ac c es s  Ng in x  ba c k .

Varnish Requ est Log

*  <<  Request > > 2 0      
-   Be gin       req 19 rx req
-   T im esta m p      Start:15871330 57.263443 0.000 0 00  0.00 000 0
-
 class="material-icons">filter_list</i></button>
_ _ </div>
  </div>
</div>

_Q:

React setstate_not_merging the_old_state into the_new state

according to_many examples, this should_work: 
const [_timeseries,_$timeseries]_= useState({hi:'lol'})

useEffect(() => {

socket.on('plot', e => {
 let keyname = Object.keys(e)[0]
 $timeseries({..._timeseries, [keyname] :_value)})
}

},_[])

console.log(_timeseries) //_here_results_in the initial state, not_the set state

The first time_it merges,_it works.
But once a new event with another_keyname_enters, it replaces_the whole thing again.
Instead of adding a new key_with [keyname], the old [keyname] is_being replaced.

A:

The problem_here_is_closures.
The callback assigned to_the useEffect closes the initial value_of _timeseries in it's the lexical_scope and it never updated.
To fix it,_you need to use the functional_useState which uses the most_updated state_within its callback:
const [_timeseries, $timeseries]_= useState({hi:'lol'})

useEffect(() =>_{
socket.on('plot', e_=> {
 let_keyname = Object.keys(e)[0]
 $timeseries(timeSeries => {...timeseries,_[keyname] : value)})
}

},_[])

 Q:

Php+Nginx+Varnish on docker-compose, ubuntu18

!Important. SOLUTION_FOUND._Everything below is_working_fine_for me._And this is_almost_the only_case_when you may copy solution from_the_question. For it read "My Configuration" section
Main_Question
On an attempt to_open_the homepage (through https_443 or http 80 does_not matter) I see 503 Varnish_error. It_looks like_Varnish cannot access Nginx back.

Varnish Request Log

*   << Request_ >> 20   _   _
- __Begin  __ _    req 19 rxreq
-_ _Timestamp     _Start: 1587133057.263443 0.000000 0.000000
-